Elevator-door-locking mechanism.



E. L. DUNN.

ELEVATOR DOOR LOCKING MECHAN APPLICATION HLED MAY 25, l9l2 ISM.

1,223, 157. Patented Apr. 17,1917. 2 EEEEEEEEEEEE I.

WITNESSES ,2. nvmvnm 2 B) 2 ma s ski EDWARD L. DUNN, 0F WORCESTER,MASSACHUSETTS, ASSIG-NOR, BY MESNE ASSIGN- MENTS, TO STANDARD PLUNGERELEVATOR COMPANY, OF WORCESTER, MASSACHU- SETTS, A CORPORATION OFMASSACHUSETTS.

ELEVATOR-DOOB-LOCKING MECHANISM.

To all whom it may concern:

Be itknown that I, EDWARD L. DUNN, a citizen of the United States,residing at Worcester, in the county of Worcester and State ofMassachusetts, have invented certain new and useful Improvements in Filevator-Door-Locking Mechanisms, of which the following is a full, clear,and exact specification.

This invention relates to elevator door locking mechanism, and hasparticular reference to means for preventing the opening of an elevatorwell door except when the car is at rest opposite the door.

The invention is especially intended for use in connection with poweroperated dumb waiter systems, wherein dumb waiter cars are required toat all times operate as high as 600 feet per minute. In such systems, itis necessary, in order to protect the attendants, to prevent them fromopening the hatchway doors except when the car has stopped at theirfloor to be loaded or unloaded. Various means for controlling the doorsof dumb waiter and other elevator systems have heretofore been devised,wherein, so far as Iam aware, the doors have been normally held locked,and automatically unlocked either as the car passed each floor, orautomatically unlocked only when the car stopped at the floors.

According to this invention, I have devised a door locking mechanism inwhich the door when closed is not locked, but which is automaticallylooked as soon as an attendant tries to open it, unless the car isstopped at that floor, whereupon the lock controlhng devices cooperatewith the car in such manner as to prevent the look from operating, andthereby'permit the door to be opened.

In the accompanying drawings, Figure l is a plan view of a portion of anelevator system equippedwith this invention;

Fig. 2 is an elevation taken along the line 2, 2 of Fig. 1, viewed inthe direction of the arrow;

Fig. 3 is an elevation showing the inven- Specifieation of LettersPatent.

PatentedApr.-17,1917.

Application filed May 25, 1912. Serial No. 699,693.

tion in normal condition with the door closed and unlocked; f

' Fig. 4 shows the door partially raised and locked; 1

Fig. 5 shows the'unlocked position with the door partially raised andthe latch held out of engagement by cooperation with the car; and pFigs. 6 and 7 are detail views, respectively, of the latch and theactuating cam,

Referring to the drawings, 1 represents the hatchway of'an elevatorcontaining the car 2 and closed by a door 3, herein shown as avertically movable door sliding between guides 4: and carried by thebuilding. I do not restrict myself to the particular form of verticallysliding door herein shown, as the invention is applicablew'ithoutmaterial modification, or any departure from the invention, toeither horizontally sliding doors or hinged doors, such applications ofthe invention not being necessary to be illustrated herein and beingcovered by the attached claims. The door 3 is normally unlocked, and isprovided with a keeper 6, which is engaged by a latch 7 pivoted on thedoor frame at 8, to hold the door locked. The pivot 8 carrying latch 7consists of a shaft, to which latch 7 is pinned, and also pinned on thisshaft 8 is an arm 9 carrying the roller 10,'the roller 10 and arm 9being positioned so as to swing into and out of the path of movement ofa cam or track 11 carried by the car 2. When the lever 9 and roller 10are in the position shown in Fig. 3,

the door is unlocked and cam 11 passes up and down the hatchway with thecar without striking the rollers 10. Mountedloosely on the shaft 8 is acam 12 (Fig. 7) having the inclined surface 13, and the flat surface 11,

and connected through a spiral spring 15 with the shaft 8 or the latch7. 16is'a stud 18 in which the shaft 8 is mounted and tending normallyto hold the roller 10 and the latch7 in the position shown in Fig. 3. InFig. 3, the normal closed position of the door is shown, wherein thekeeper 6 is some distance below the lower end of the latch 7 and theroller 10 is out of the path of movement of the cam 11. Also in thisposition, the cam surface 13 rests on the stud or roller 16. If the dooris pushed upward, the effect is to cause the stud 16 to ride up on thecam 12 to the flat portion 14, thereby throwing the parts into theposition shown in Fig. 2, spring 15 being strong enough to overcomespring 17. The door is thus locked against further upward movementbecause of the latch 7 coming into the path of the keeper 6, while thearm 9 and roller 10 are thrown outward to the position shown in Fig. 4.It will thus be seen that the door is looked as soon as the attendantcommences to move it upward. If, however, the cam 11 is opposite theroller 10, it will be seen that the latch 7 will not be thrown into thepath of the keeper 6, so that the door can be opened, the stud 16 movingaway from the cam 12 and the keeper 6 passing over the cam 12 bothduring the opening movement of the door and the closing movement. 19represents an adjustable stop mounted on the end of shaft 8 which can beset to regulate the throw of spring 17, for the purpose of setting theroller 10 the proper distance from the vertical path of cam ll, as shownin Fig. 2. The cam 12 has a certain amount of lost motion between it andlatch 7, before it operates latch 7, this being provided-for by theteeth 22, 23 which are cut away to the de sired extent.

Having thus described my invention, I declare that what I claim as newand desire to secure by Letters Patent is 1. The combination with anelevator door, of normally unlocked locking means actuated to lockingposition by opening movement of the door, and means for holding saidmeans unlocked. when the elevator car is at said door.

2. The combination with an elevator car, of a door, normally inoperativemeans controlled by the door for locking the door against full openingwhile permitting a limited movement thereof, and means carried by thecar for holding said locking means inoperative.

3. The combination with an elevator car, of a normally free door, meansfor locking the door upon opening movement thereof, and means carried bythe car for holding said locking means inoperative when the door isopened.

4. The combination with, an elevator car, of a normally free door, akeeper carried by said door, a latch controlled by opening movementof'said door to engage said keeper to lock the door, and means carriedby the car for preventing engagement of said keeper and said latch.

5. The combination with an elevator car,

. of a normally free door, locking means opthe door and the other .tothe casement and being normally disengaged, means for throwing the latchinto the keeper upon movement of the door, and means independent of thedoor for holding the latch out of the keeper when the door is to beopened.

7. A door locking mechanism comprising a keeper, and a'latch, one beingattached to the door and the other to the easement and being normallydisengaged, means for throwing the latch into the keeper upon movementof the door, and means controlled by a movable oar opposit the door forholding the latch out of the keeper when the door is to r be opened.

8. The combination with a car, of a door, means controlled by movementof the. door for looking it against opening, and means carried by thecar for rendering said locking means lnoperative.

9. A door locking mechanism comprising a keeper, and a latch, one beingattached to the door and the other to the easement, a spring normallyholding the latch out of engagement with the keeper, means operated bythe door for throwing the latch into the keeper against said spring, anda spring connectmg said means with the latch and stronger than saidfirst spring.

10. A door locking mechanism comprising a keeper, and a latch, one beingattached to the door and the other to the casement and be ng normallydisengaged, a rock shaft carrying said latch, an arm carried by saidrock shaft, a car having means for limiting move ment of said latchtoward the keeper, and

ing a keeper, and a latch, one being attached yielding connectionbetween said means and to the door and the other to the easement, thelatch. 10 and being normally disengaged, means oper- In testimonywhereof I aflix my signature ated by movement of the door from closed inpresence of two witnesses.

position for throwing the latch into the EDWARD L; DUNN. keeper to stopthe door, means engageable Witnesses:

with an elevator car for preventing throw- H. C. EGAN,

ing of the latch into the keeper, and a G. N. KERR.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D, G.

